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971.
Tuberculosis and leprosy are chronic bacterial infectious diseases which represent major health problems worldwide. It is generally accepted that, on the one hand, effective vaccination strategies are required for satisfactory control of these diseases and, on the other hand, that currently available vaccination measures are insufficient for this purpose. Ideally, a subunit vaccine should be designed which is composed of one or a few protective antigens. In this brief treatise our approach towards the identification of antigens with potential value for vaccine design is described. It comprises high resolution fractionation by two-dimensional gel electrophoresis, transfer of separated fractions by electroelution and testing of separated fractions with viable T cells and accessory cells. Using this approach we find: (1) multiple antigens are recognized by T cells from leprosy and tuberculosis patients as well as healthy contacts; (2) apparently, suppressive antigens exist in leprosy; (3) an antigen cluster which is apparently indicative for immunity against M. tuberculosis is present among secreted proteins. We hope that further improvement of this methodology will help in the rational design of subunit vaccines against tuberculosis and leprosy.  相似文献   
972.
973.
African Americans are at increased risk for cancer and represent an important target population for programs such as Healthy People 2000, the Cancer Information Service (CIS), and the 5 a Day for Better Health Initiative. Yet, awareness of such programs among rural blacks is unknown. This study assessed awareness of these programs and determined related knowledge and beliefs among rural African Americans. It was undertaken as part of the baseline survey for the Black Churches United for Better Health project, a National Cancer Institute-funded initiative. A minority of respondents (n = 3737) demonstrated name recognition of Healthy People 2000 (23.4%), the CIS (42.4%), and the 5 a Day Program (40.7%). Far fewer (7.4%) were able to correctly identify the recommended daily number of servings of fruits and vegetables. Reported family history of cancer was associated with a greater tendency believe that eating more fruits and vegetables can prevent disease. These findings underscore the need for efforts to reach the rural black community with culturally sensitive and stage appropriate cancer prevention messages. Knowledge of family history of cancer may play an important role in targeting subgroups and delivering effective cancer prevention messages.  相似文献   
974.
975.
976.
114 patients aged over 75 underwent surgery for aneurysm of the infra-renal abdominal aorta in the University Teaching Hospitals in Nantes and Angers between 1979 and 1988. A retrospective study of these patients was performed to evaluate the immediate and long-term results. The mean age of the patients was 79 (+/- 4) years, the oldest being 94. 70% were men. Half of the patients underwent emergency or semi-emergency surgery (52 cases). Cardiovascular factors (in particular coronary insufficiency in 17% of cases) were the most common risk factors. In all cases grafting after laying open the aneurysm was performed, with an aorto-aortic graft in 32% of patients, an aorto-iliac graft in 37% or an aorto-bifemoral graft in 27% of patients. Combined intestinal revascularisation was performed in 10% of case either involving the inferior mesenteric artery or at least one internal iliac artery; renal revascularisation was performed in 3.5% of cases. 75% of patients underwent simple grafting. The mean duration of hospitalisation was 14 days (+/- 6), including a mean period of 7 days in ICU. 36 patients (31%) died in the first post-operative month. The mortality rate in patients who underwent emergency surgery for a complication of the aneurysm (essentially rupture) was 61% versus 6' for elective surgery. 96% of the patients who survived the first post-operative month were independent at the end of the study or at the time of their death.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
977.
978.
979.
Intravitreal injection of interferon gamma (IFN-gamma) induces increased expression of Class II major histocompatibility complex (Ia) antigen expression on corneal endothelial cells and stromal fibroblasts. In contrast, IFN-gamma has no detectable effect on Ia antigen expression in epithelium. Induction of Ia antigen expression was rapid with increases detectable as early as 6-12 hours after a single injection of 1 x 10(5) units. Expression peaked at 24-48 hours and decreased to background levels by 120 hours. The Ia antigen expression increased in a dose-dependent manner, and IFN-gamma treatment also induced the synthesis of increased amounts of a 65-kilodalton (kD) protein in the cornea. Increased levels of this 65-kd protein are seen as early as 12 hours after treatment and can be induced with as little as 1 x 10(2) units of IFN-gamma. The function of the 65-kd protein is unknown. This model should be useful in studies on in vivo modulation of Ia antigen expression.  相似文献   
980.
The natural history of uveitis   总被引:8,自引:0,他引:8  
Summary Inflammatory diseases of the eye were known to the ancients, but only recently have the underlying mechanisms to this problem become better defined. During the middle portion of this century, most cases of uveitis thought to be caused by infectious agents, such as those responsible for syphilis and tuberculosis. Since then, it has become clear that endogenous mechanisms of immunomodulation play an important role in these disorders, which along with environmental and genetic factors make up an important triad. Animals studies have indicated the pivotal role of the T-cell in many of these disorders. The development of T-cell lines has helped to further delineate cell to cell interactions that occur during an ocular inflammatory event. The presence in the eye of uveitogenic antigens raises the strong possibility of autoimmune driven processes as well, similar to what is seen in the animal models. The better understanding of ocular inflammatory mechanisms has led to improved therapeutic strategies, including Sandimmune, and more recently Cyclosporine G, a related compound that may be less nephrotoxic. Newer therapeutic strategies will focus on even more novel modes of immunomodulation, probably without the use of medications.  相似文献   
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